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<title>Atari "Sally" (6502) Instruction Set</title>
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<h1><center><b>Atari "Sally" (6502) Instruction Set</b></center></h1>

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<h2><b>Op-Code Table</b> (arranged in op-code order):</h2>

<table border cellpadding=5 width="100%">
<tr align="center">
<td width="7%">\&nbsp;LSD<br>
MSD&nbsp;\</td>
<td width="7%">0</td>
<td width="7%">1</td>
<td width="7%">2</td>
<td width="7%">3</td>
<td width="7%">4</td>
<td width="7%">5</td>
<td width="7%">6</td>
<td width="7%">7</td>
<td width="7%">8</td>
<td width="7%">9</td>
<td width="7%">A</td>
<td width="7%">B</td>
<td width="7%">C</td>
<td width="7%">D</td>
<td width="7%">E</td>
<td width="7%">F</td>
<td width="7%">LSD&nbsp;/<br>
/&nbsp;MSD</td></tr>
<tr>
<td align="center">0</td>
<td>BRK</td>
<td>ORA<br>
(IND,X)</td>
<td>JAM *</td>
<td>SRA *<br>
(IND,X)</td>
<td>NOP *<br>
Z-Page</td>
<td>ORA<br>
Z-Page</td>
<td>ASL<br>
Z-Page</td>
<td>SRA *<br>
Z-Page</td>
<td>PHP</td>
<td>ORA<br>
IMM</td>
<td>ASL<br>
A</td>
<td>ANC *<br>
IMM</td>
<td>NOP *<br>
ABS</td>
<td>ORA<br>
ABS</td>
<td>ASL<br>
ABS</td>
<td>SRA *<br>
ABS</td>
<td align="center">0</td></tr>
<tr>
<td align="center">1</td>
<td>BPL</td>
<td>ORA<br>
(IND),Y</td>
<td>JAM *</td>
<td>SRA *<br>
(IND),Y</td>
<td>NOP *<br>
Z-Page,X</td>
<td>ORA<br>
Z-Page,X</td>
<td>ASL<br>
Z-Page,X</td>
<td>SRA *<br>
Z-Page,X</td>
<td>CLC</td>
<td>ORA<br>
ABS,Y</td>
<td>NOP *</td>
<td>SRA *<br>
ABS,Y</td>
<td>NOP *<br>
ABS,X</td>
<td>ORA<br>
ABS,X</td>
<td>ASL<br>
ABS,X</td>
<td>SRA *<br>
ABS,X</td>
<td align="center">1</td></tr>
<tr>
<td align="center">2</td>
<td>JSR<br>
ABS</td>
<td>AND<br>
(IND,X)</td>
<td>JAM *</td>
<td>RLA *<br>
(IND,X)</td>
<td>BIT<br>
Z-Page</td>
<td>AND<br>
Z-Page</td>
<td>ROL<br>
Z-Page</td>
<td>RLA *<br>
Z-Page</td>
<td>PLP</td>
<td>AND<br>
IMM</td>
<td>ROL<br>
A</td>
<td>ANC *<br>
IMM</td>
<td>BIT<br>
ABS</td>
<td>AND<br>
ABS</td>
<td>ROL<br>
ABS</td>
<td>RLA *<br>
ABS</td>
<td align="center">2</td></tr>
<tr>
<td align="center">3</td>
<td>BMI</td>
<td>AND<br>
(IND),Y</td>
<td>JAM *</td>
<td>RLA *<br>
(IND),Y</td>
<td>NOP *<br>
Z-Page,X</td>
<td>AND<br>
Z-Page,X</td>
<td>ROL<br>
Z-Page,X</td>
<td>RLA *<br>
Z-Page,X</td>
<td>SEC</td>
<td>AND<br>
ABS,Y</td>
<td>NOP *</td>
<td>RLA *<br>
ABS,Y</td>
<td>NOP *<br>
ABS,X</td>
<td>AND<br>
ABS,X</td>
<td>ROL<br>
ABS,X</td>
<td>RLA *<br>
ABS,X</td>
<td align="center">3</td></tr>
<tr>
<td align="center">4</td>
<td>RTI</td>
<td>EOR<br>
(IND,X)</td>
<td>JAM *</td>
<td>SLO *<br>
(IND,X)</td>
<td>NOP *<br>
Z-Page</td>
<td>EOR<br>
Z-Page</td>
<td>LSR<br>
Z-Page</td>
<td>SLO *<br>
Z-Page</td>
<td>PHA</td>
<td>EOR<br>
IMM</td>
<td>LSR<br>
A</td>
<td>ASR *<br>
IMM</td>
<td>JMP<br>
ABS</td>
<td>EOR<br>
ABS</td>
<td>LSR<br>
ABS</td>
<td>SLO *<br>
ABS</td>
<td align="center">4</td></tr>
<tr>
<td align="center">5</td>
<td>BVC</td>
<td>EOR<br>
(IND),Y</td>
<td>JAM *</td>
<td>SLO *<br>
(IND),Y</td>
<td>NOP *<br>
Z-Page,X</td>
<td>EOR<br>
Z-Page,X</td>
<td>LSR<br>
Z-Page,X</td>
<td>SLO *<br>
Z-Page,X</td>
<td>CLI</td>
<td>EOR<br>
ABS,Y</td>
<td>NOP *</td>
<td>SLO *<br>
ABS,Y</td>
<td>NOP *<br>
ABS,X</td>
<td>EOR<br>
ABS,X</td>
<td>LSR<br>
ABS,X</td>
<td>SLO *<br>
ABS,X</td>
<td align="center">5</td></tr>
<tr>
<td align="center">6</td>
<td>RTS</td>
<td>ADC<br>
(IND,X)</td>
<td>JAM *</td>
<td>RRA *<br>
(IND,X)</td>
<td>NOP *<br>
Z-Page</td>
<td>ADC<br>
Z-Page</td>
<td>ROR<br>
Z-Page</td>
<td>RRA *<br>
Z-Page</td>
<td>PLA</td>
<td>ADC<br>
IMM</td>
<td>ROR<br>
A</td>
<td>ARR *<br>
IMM</td>
<td>JMP<br>
Indirect</td>
<td>ADC<br>
ABS</td>
<td>ROR<br>
ABS</td>
<td>RRA *<br>
ABS</td>
<td align="center">6</td></tr>
<tr>
<td align="center">7</td>
<td>BVS</td>
<td>ADC<br>
(IND),Y</td>
<td>JAM *</td>
<td>RRA *<br>
(IND),Y</td>
<td>NOP *<br>
Z-Page,X</td>
<td>ADC<br>
Z-Page,X</td>
<td>ROR<br>
Z-Page,X</td>
<td>RRA *<br>
Z-Page,X</td>
<td>SEI</td>
<td>ADC<br>
ABS,Y</td>
<td>NOP *</td>
<td>RRA *<br>
ABS,Y</td>
<td>NOP *<br>
ABS,X</td>
<td>ADC<br>
ABS,X</td>
<td>ROR<br>
ABS,X</td>
<td>RRA *<br>
ABS,X</td>
<td align="center">7</td></tr>
<tr>
<td align="center">8</td>
<td>NOP *<br>
IMM</td>
<td>STA<br>
(IND,X)</td>
<td>NOP *<br>
IMM</td>
<td>SAX *<br>
(IND,X)</td>
<td>STY<br>
Z-Page</td>
<td>STA<br>
Z-Page</td>
<td>STX<br>
Z-Page</td>
<td>SAX *<br>
Z-Page</td>
<td>DEY</td>
<td>NOP *<br>
IMM</td>
<td>TXA</td>
<td>AXE *<br>
IMM</td>
<td>STY<br>
ABS</td>
<td>STA<br>
ABS</td>
<td>STX<br>
ABS</td>
<td>SAX *<br>
ABS</td>
<td align="center">8</td></tr>
<tr>
<td align="center">9</td>
<td>BCC</td>
<td>STA<br>
(IND),Y</td>
<td>JAM *</td>
<td>AX7 *<br>
(IND),Y</td>
<td>STY<br>
Z-Page,X</td>
<td>STA<br>
Z-Page,X</td>
<td>STX<br>
Z-Page,Y</td>
<td>SAX *<br>
Z-Page,Y</td>
<td>TYA</td>
<td>STA<br>
ABS,Y</td>
<td>TXS</td>
<td>XS7 *<br>
ABS,Y</td>
<td>SY7 *<br>
ABS,X</td>
<td>STA<br>
ABS,X</td>
<td>SX7 *<br>
ABS,Y</td>
<td>AX7 *<br>
ABS,Y</td>
<td align="center">9</td></tr>
<tr>
<td align="center">A</td>
<td>LDY<br>
IMM</td>
<td>LDA<br>
(IND,X)</td>
<td>LDX<br>
IMM</td>
<td>LAX *<br>
(IND,X)</td>
<td>LDY<br>
Z-Page</td>
<td>LDA<br>
Z-Page</td>
<td>LDX<br>
Z-Page</td>
<td>LAX *<br>
Z-Page</td>
<td>TAY</td>
<td>LDA<br>
IMM</td>
<td>TAX</td>
<td>XEA *<br>
IMM</td>
<td>LDY<br>
ABS</td>
<td>LDA<br>
ABS</td>
<td>LDX<br>
ABS</td>
<td>LAX *<br>
ABS</td>
<td align="center">A</td></tr>
<tr>
<td align="center">B</td>
<td>BCS</td>
<td>LDA<br>
(IND),Y</td>
<td>JAM *</td>
<td>LAX *<br>
(IND),Y</td>
<td>LDY<br>
Z-Page,X</td>
<td>LDA<br>
Z-Page,X</td>
<td>LDX<br>
Z-Page,Y</td>
<td>LAX *<br>
Z-Page,Y</td>
<td>CLV</td>
<td>LDA<br>
ABS,Y</td>
<td>TSX</td>
<td>LAS *<br>
ABS,Y</td>
<td>LDY<br>
ABS,X</td>
<td>LDA<br>
ABS,X</td>
<td>LDX<br>
ABS,Y</td>
<td>LAX *<br>
ABS,Y</td>
<td align="center">B</td></tr>
<tr>
<td align="center">C</td>
<td>CPY<br>
IMM</td>
<td>CMP<br>
(IND,X)</td>
<td>NOP *<br>
IMM</td>
<td>DCP *<br>
(IND,X)</td>
<td>CPY<br>
Z-Page</td>
<td>CMP<br>
Z-Page</td>
<td>DEC<br>
Z-Page</td>
<td>DCP *<br>
Z-Page</td>
<td>INY</td>
<td>CMP<br>
IMM</td>
<td>DEX</td>
<td>ASX *<br>
IMM</td>
<td>CPY<br>
ABS</td>
<td>CMP<br>
ABS</td>
<td>DEC<br>
ABS</td>
<td>DCP *<br>
ABS</td>
<td align="center">C</td></tr>
<tr>
<td align="center">D</td>
<td>BNE</td>
<td>CMP<br>
(IND),Y</td>
<td>JAM *</td>
<td>DCP *<br>
(IND),Y</td>
<td>NOP *<br>
Z-Page,X</td>
<td>CMP<br>
Z-Page,X</td>
<td>DEC<br>
Z-Page,X</td>
<td>DCP *<br>
Z-Page,X</td>
<td>CLD</td>
<td>CMP<br>
ABS,Y</td>
<td>NOP *</td>
<td>DCP *<br>
ABS,Y</td>
<td>NOP *<br>
ABS,X</td>
<td>CMP<br>
ABS,X</td>
<td>DEC<br>
ABS,X</td>
<td>DCP *<br>
ABS,X</td>
<td align="center">D</td></tr>
<tr>
<td align="center">E</td>
<td>CPX<br>
IMM</td>
<td>SBC<br>
(IND,X)</td>
<td>NOP *<br>
IMM</td>
<td>ISB *<br>
(IND,X)</td>
<td>CPX<br>
Z-Page</td>
<td>SBC<br>
Z-Page</td>
<td>INC<br>
Z-Page</td>
<td>ISB *<br>
Z-Page</td>
<td>INX</td>
<td>SBC<br>
IMM</td>
<td>NOP</td>
<td>SBC *<br>
IMM</td>
<td>CPX<br>
ABS</td>
<td>SBC<br>
ABS</td>
<td>INC<br>
ABS</td>
<td>ISB *<br>
ABS</td>
<td align="center">E</td></tr>
<tr>
<td align="center">F</td>
<td>BEQ</td>
<td>SBC<br>
(IND),Y</td>
<td>JAM *</td>
<td>ISB *<br>
(IND),Y</td>
<td>NOP *<br>
Z-Page,X</td>
<td>SBC<br>
Z-Page,X</td>
<td>INC<br>
Z-Page,X</td>
<td>ISB *<br>
Z-Page,X</td>
<td>SED</td>
<td>SBC<br>
ABS,Y</td>
<td>NOP *</td>
<td>ISB *<br>
ABS,Y</td>
<td>NOP *<br>
ABS,X</td>
<td>SBC<br>
ABS,X</td>
<td>INC<br>
ABS,X</td>
<td>ISB *<br>
ABS,X</td>
<td align="center">F</td></tr>
<tr align="center">
<td>MSD&nbsp;/<br>
/&nbsp;LSD</td>
<td>0</td>
<td>1</td>
<td>2</td>
<td>3</td>
<td>4</td>
<td>5</td>
<td>6</td>
<td>7</td>
<td>8</td>
<td>9</td>
<td>A</td>
<td>B</td>
<td>C</td>
<td>D</td>
<td>E</td>
<td>F</td>
<td>\&nbsp;MSD<br>
LSD&nbsp;\</td></tr></table>

<h3>Notes:</h3>

<p>* Undocumented instruction.  The behavior of these opcodes was observed on
an Atari 800.  It may vary with other 6502-based CPU's.

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